New Scientist says our galaxy contains about 500 Cepheid variables—giant pulsating stars. Astronomers know how many exist because these objects shine bright enough at the peak of their variability to be seen from as far as 60 million light years away. Learned says that highly advanced aliens could alter a Cepheid’s rate of variability by blasting it with something of great energy, like a beam of neutrinos. If they could control the rate, they could encode binary 0’s and 1’s into the stars, and communicate across the galaxy.
While the suggestion of galactic Internet may seem far-fetched—or outright preposterous—at least this is one hypothesis about aliens that scientists could check. Astronomers have studied the rates of variability in our galaxy’s Cepheids for almost a century, so they could monitor them to see if there’s an unnatural change, and perhaps catch E.T. using them as communications beacons.
The thought of galactic communication is exciting, but still: When a representative of SETI shrugs off an idea as a “nice suggestion,” that should give everyone an idea of just how likely it is. However, according to a New York Times op-ed, we need to shift more of our national security attention to preventing attacks by aliens—so maybe if they’re sending battle plans through stars, we could intercept them.